Cardiovascular disease is the leading cause of death in the United States and claims the lives of more than 600,000 Americans each year. According to the American Heart Association (AHA), more than five million Americans are diagnosed with heart valve disease each year, and diseases of the aortic and mitral valves are the most prevalent. Combined, aortic and mitral valve diseases affect more than five percent of the U.S. population.
The proper assessment and diagnosis of heart valve operation and the condition of surrounding cardiovascular tracts are essential for ensuring high quality patient care. To this end, several imaging modalities may be used to inspect the condition and function of heart valves and the surrounding vasculature. Transthoracic and transesogophogeal echocardiography, for example, use ultrasound technology to create two- and/or three-dimensional images of heart valves and the surrounding inflow/outflow tracts (e.g., left ventricular outflow tract, ascending aorta). Further, computed tomography (CT) and magnetic resonance imaging (MRI) may also be used.
All imaging modalities have strengths and weaknesses that may limit their ability to provide a complete and comprehensive assessment of anatomic and/or physiologic condition. The spatial resolution of echocardiographic images, for example, may inhibit a detailed analysis of functional operation, especially for highly calcified heart valves. Computed tomography may provide higher resolution images than echocardiography, but CT imaging studies are more costly and expose patients to radiation that is potentially harmful. In addition, contrast agents, which may be highly nephrotoxic and may be associated with alterations in renal function, are often used during CT examinations. Hence, new and novel methods that enable an accurate anatomic and physiological assessment of heart valves and the surrounding vasculature, while not exposing patients to excessive risks or prohibitive costs, are desirable.
Patients diagnosed with symptomatic and clinically significant heart valve abnormalities may be candidates for valvular repair or replacement. When repair or replacement is indicated, an accurate and complete understanding of valvular anatomy is essential to ensure a favorable outcome. In addition, the anatomic and physiologic characteristics of the inflow and outflow tracts that surround the heart valve(s) must also be understood.
New methods for assessing the anatomic and/or physiologic condition of native and prosthetic heart valves and the surrounding inflow/outflow tracts should enable more accurate and precise treatment planning. These new methods may complement and/or work in conjunction with existing methods, or they may stand alone. Regardless, such technologies must provide clear and demonstrable benefits to the physician(s) who treat patients with heart valve disease and/or diseases of the surrounding cardiac tracts. Further, new technologies must not expose patients to excessive medical risks and should be cost effective.
Therefore, to improve diagnostic and treatment capabilities, it is desirable to have a system for quickly and accurately assessing the physiological function, condition, and morphology of heart valves and the surrounding inflow/outflow tracts, which thereby enables the proper diagnosis of heart valve disease and, if warranted, facilitates treatment planning.